1. Field of the Invention
This invention pertains generally to the field of gas cutting torches such as the well known and widely used oxy-acetylene torches. More particularly, the present invention is a gas torch tip protector that allows the torch to be handled and used in more rugged and extreme environments than was heretofore possible.
2. Description of the Related Art
Nearly from the beginnings of the bronze age, mankind has pursued better ways to work with metal. Metal working has in no small part included ways of bonding together and separating metals. One early bonding technique involved the creation of lower melt alloys that could be used to braze metal together. Brazing and soldering are quite effective for relatively soft and malleable materials such as copper. However, with the iron age came much harder and stronger steel compositions. The strength of a brazed or soldered connection is in most cases far weaker than the intrinsic strength of steel. Consequently, brazing is for many steel applications inadequate. Understandably then, with the improvements in metals have come many additional improvements in bonding and separating.
One quite old technique for bonding and separating metals is the use of a torch. While there were early single gas torches that burned various combustible materials to generate heat, over time certain chemicals were developed that offered more capability and flexibility. Premier among these are acetylene torches that combust acetylene gas with oxygen gas. These torches, which were invented more than a century ago, still remain the most commonly used type of torch. They are capable of burning at extremely high temperatures of approximately 6,000 degrees Fahrenheit, which is sufficient to easily melt and bond many metals, including all common steel alloys. Furthermore, the gases may be stored in relatively small canisters or cylinders, and are readily and, with minimal proper preparation, quite safely and easily transported. No energy source is required to operate the torch other than a hand-held sparker or igniter that is used to ignite the gases. The oxyacetylene torch may further be used in nearly any environment, meaning adverse weather does not inhibit the use of the torch. The self-contained nature, relative ease of transport, and ability to operate in adverse weather means the oxyacetylene torch can be used in environments that are not able to support the operation of the many newer and more sophisticated torches. For example, various arc, Metal-Inert-Gas (MIG), Tungsten-Inert-Gas (TIG) and plasma welders have been developed that have great utility, but these types of welders are generally significantly bulkier than an oxyacetylene torch, are less resistant to adverse weather and environment, and they require access to relatively high power electrical sources, some even requiring an industrial three-phase power source. Since many job sites are not sheltered from the weather or have ready access to high power electrical connection, these newer welding apparatus are limited to use within an adequately wired and sheltered work shop or the like.
While oxyacetylene torches have been very beneficial in welding together metals such as steel, these torches also enable another very useful process for separating steel. When an oxyacetylene torch is used for cutting, a modern cutting torch tip will commonly include a plurality of smaller orifices surrounding a central jet. The smaller orifices carry a mix of oxygen and acetylene, and this mix is used to preheat the steel to a cherry-red. Then the operator presses a trigger that opens the flow of oxygen through the larger central jet orifice in the torch tip, substantially increasing the flow of oxygen relative to acetylene. This makes the torch extremely oxidizing. The large flow of oxygen through this larger central jet introduces the excess oxygen to the heated steel, causing the steel to literally burn and release a great deal of additional heat. The excess oxygen forms iron oxide that has a melting point much lower than that of steel. Consequently, this molten iron oxide is removed from the metal substrate simply by the pressure from the gas flow. This means that the torch can be switched from a neutral or even slightly reducing mix of oxygen and acetylene for heating, welding or bonding to an oxidizing flame that is very oxygen rich. This can be done at will by the welder, allowing the torch to be used not only for bonding but also for cutting. As may be understood then, this technique is extremely energy and time efficient for cutting steel, making the oxyacetylene torch preferred for most cutting torches, and far more efficient at cutting heavier steel than other techniques. The oxyacetylene torch is still today, more than a century after development, one of the most flexible and useful tools in steel working.
While there have been oxyacetylene torches for more than a century, and while these torches are often the tool of choice for remote job sites or for cutting steel, they do suffer from one vexing limitation. The orifices in the torch tip, particularly the smaller orifices surrounding the central jet but also including the central jet, may be easily clogged with dirt if the torch tip is allowed to drag on the ground. However, and as already noted herein above, adverse work environments are best suited for this type of torch. Consequently, all too commonly a welder will unintentionally drag the torch tip, such as when climbing into or out of a depression or hole in the ground or when otherwise transporting the torch. In such case, the torch may not perform optimally, and the operator may lose significant time either cleaning or replacing a clogged or damaged torch tip. In spite of the more than one hundred years of use of the oxyacetylene torch, this still today remains an unresolved problem in the field of cutting torches for welders.
U.S. Pat. No. 3,375,090 by Marra Jr, entitled “Protective devices for torch tips”; and U.S. Pat. No. 4,585,410 by Baker et al, entitled “Torch tip saver”, the teachings and contents which are incorporated herein by reference, describe torch tip protectors that help to shield torch tip orifices from cutting debris, while simultaneously protecting against damage to the torch tip if the tip is accidentally rapped against a hard surface. Unfortunately, these torch tip devices are open to the torch tip orifices, and so do not prevent debris from clogging the torch tip during transport.
In the broader field of torches, including single gas torches and electrical plasma torches, there have been a number of additional patents on protectors for torch tips. Exemplary U.S. patents, the teachings and contents of each which are incorporated herein by reference, include U.S. Pat. No. 4,891,489 by Bollinger et al, entitled “Shield cup protector apparatus for plasma arc torch”; and U.S. Pat. No. 5,856,647 by Luo, entitled “Drag cup for plasma arc torch”. Similar to the Marra and Baker et al patent, these patents are also open to the torch tip, and are installed during torch operation, protecting the torch tip against accidental impact and other useful benefit but failing to protect the torch tip during transport.
Another U.S. Pat. No. 5,741,128 by Tsai, entitled “Hand gas torch”, the teachings and contents which are incorporated herein by reference, describes a small hand-held single gas torch such as might be used for hobby brazing, combusting, or heating processes. This type of torch will reach much lower temperatures than that of an oxyacetylene or other dual gas torch. The Tsai torch includes a nozzle cap that is connected by a chain, and is used to cover the flame nozzle assembly when the hand gas torch is not in use. While the illustrated cover is undoubtedly of great utility in the single gas torch, there is little teaching for the application to oxyacetylene torches. The Tsai torch tip cover is cylindrical, meaning that it must have relatively close tolerances on the inside diameter to properly form a friction engagement with the outer tube of the flame nozzle assembly. For a hobby torch that is used primarily for relatively lower temperature heating or combusting, and which is transported in a clothing pocket, this is quite viable. However, in using an oxyacetylene cutting torch, the oxyacetylene torch tip is exposed to occasional bits of molten metal or slag that can stick to the torch tip, and the oxyacetylene torch tip, as aforementioned, may be dragged along the ground or the like. Furthermore, the extremely high temperatures generated by the oxygen and acetylene combustion will heat any outer tubes around the flame nozzle assembly or torch tip, and without the use of very expensive materials will lead to deformation of the metal from repeated heating and cooling. Consequently, a torch tip cover such as illustrated by Tsai will only have utility in an oxyacetylene torch when the torch tip is new, and will no longer be operative once the cutting torch has been used.
In addition to the aforementioned patents, Webster's New Universal Unabridged Dictionary, Second Edition copyright 1983, is additionally incorporated herein by reference in entirety for the definitions of words and terms used herein.